A marine hose is used to transport crude oil or the like by sea by connecting a tanker on the sea to a facility on the land. An annular-shaped floater designed to have predetermined buoyancy may be externally fitted onto a predetermined position on the marine hose in order to form an appropriate hose line among other purposes. Conventionally, this floater has a structure in which respective one ends of semiannular floating bodies are connected to each other by use of a hinge mechanism or the like, and in which respective other ends are connected to each other by use of an end coupling member to thereby form an annular shape (see Patent Document 1, for example).
Meanwhile, in manufacture of a marine hose, the marine hose is difficult to be formed into a circular shape in cross section, or even into a shape close to a perfect circle, at high accuracy. Even marine hoses of the same specification have variation in circularity. Moreover, a single marine hose has variation in the circularity depending on the position. Accordingly, having a predetermined shape when formed into an annular shape, the conventional bisected type floater may not be able to be fitted externally to the marine hose if the circularity of the marine hose falls below a certain level. There has therefore been a problem that a cumbersome operation such as alteration of the end coupling member is required to achieve fitting. Moreover, such a floater requires preparation of dedicated floaters depending on the outside diameter size of the marine hose in order to conform to the outside diameter of the marine hose. This causes a problem that huge costs are required for manufacturing and maintenance management.    Patent Document 1: Japanese patent application Kokai publication No. Sho 53-89023